Apparatus for compression-molding a powder within containers

ABSTRACT

A plurality of dies are mounted on an intermittently rotating table in circumferentially equally spaced relation and below each die is provided a powder molding mechanism comprising a vertically movable molding tube extending into said die at its top end and a vertically movable center pin extending through said molding tube with the top end thereof located within said die. Each die is charged with a powder at one station and shifted to another station upon the intermittent rotation of said table where a cylindrical container with a bottom is placed in the die with the open end thereof facing downward, and then further shifted to still another station where the powder charged in the die is moved into the container and compression-molded therein by said molding mechanism, whereby the steps of charging the powder into the die, moving the powder into the container and compression-molding the powder within said container are carried out successively during one complete rotation of said table, and hence operation efficiency can be enhanced and the apparatus is highly adapted to mass production.

United States Patent [1 1 Okubo et al.

[451 Apr. 2 4,197?

[ 1 APPARATUS FOR COMPRESSION- MOLDING A POWDER WITHIN CONTAINERS [75]Inventors: Kei Okubo, Neyagawa-shi; Toru Horiguchi, Kadoma-shi; MiyojiNakai, Neyagawa-shi; Haruhisa Shimada,0saka, all of J apan [73]Assignee: Matsushita Electric Industrial Co.,

Ltd., Osaka. Japan [22] Filed: Dec. 10,1969

[21] Appl.No.: 883,799

[30] Foreign Application Priority Data Dec. 13, 1968 Japan ..43/9l862[52] US. Cl. ..425/36l, 425/78, 425/355, 425/424, 425/432, 425/431 [51]Int. Cl. ..B29c l/l4, B29c 3/04, 1329C 6/00 [58] Field ofSearch..18/l6.5,5 RR, R, 18/20 B, 20 C, 20 G, 20 H, 20 P, 20 RR, 20

S, 20 T, DIG. 47, 23, 16.7; /66, 67,

[56] References Cited UNITED STATES PATENTS 2,449,008 9/1948 Pecker Ct211. 1 8/20 T X 3,445,893 5/1969 Talmage .l8/l6.5 X 2,954,585 10/1960Simpson "18/20 (1 917,627 4/1909 Lizottc 1 8/20 F 2,875,471 3/1959Crowther 18/20 '1 3,084,387 4/1963 Tochner et a1 18/20 T X 3,537,13711/1970 Lancesseur 18/20 (TX H1955 Gilbert 18/5 PP X 5/1956 3,382,5335/1968 Fyfe ct a1 ..l8/2O P X 3,522,631 8/1970 Niclas ..18/2O C2,122,874 7/1938 Whipple 18/165 X 2,900,664 8/1959 Hampel et al....l8/16 R 3,183,570 5/1965 Vogt 18/165 X 3,495,308 2/1970 Schulze..18/16.5 X 2,325,687 8/1943 Kux ..18/DIG. 35

FOREIGN PATENTS OR APPLICATIONS 739,71 1 1955 Great Britain ..18/20 RRPrimary ExaminerRobert L. Spicer, Jr. Att0rneyStevens, Davis, Miller &Mosher 57] ABSTRACT A plurality of dies are mounted on an intermittentlyrotating table in circumferentially equally spaced relation and beloweach die is provided a powder molding mechanism comprising a verticallymovable molding tube extending into said die at its top end and avertically movable center pin extending through said molding tube withthe top end thereof located within said die. Each die is charged with apowder at one station and shifted to another station upon theintermittent rotation of said table where a cylindrical container with abottom is placed in the die with the open end thereof facing downward,and then further shifted to still another station where the powdercharged in the die is moved into the container and compressionmoldedtherein by said molding mechanism, whereby the steps of charging thepowder into the die, moving the powder into the container andcompression-molding the powder within said container are carried outsuccessively during one complete rotation of said tablc, and henceoperation efficiency can be enhanced and the apparatus is highly adaptedto mass pr0duction.

5 Claims, 12 Drawing Figures Gora "18/206 X 7 Patented April 24, 1973 6Sheets-Sheet 1 FIG.

KEI OKUB'O TORU HORI'GUCHI MlYOJl NAK'AI HARUHISA SHIMADA Patented April24, 1973 3,729,281

6 Sheets-Sheet 2 6 Sheets-Sheet 5 klll-l FIG 3 Patented April 24-, 1973Patented April 24, 1973 6 Sheets-Sheet 4 FIG; 6 28 FIG. 5

FIG. 4

mi .7 r HT VA Patented April 24, 1973 6 Sheets-Sheet 6 FIG. l2

APPARATUS FOR COMPRESSION-MOLDING A POWDER WITHIN CONTAINERS The presentinvention relates to a powder molding apparatus by which a powder iscompression-molded into a predetermined shape within a container, andwhich comprises a rotary table, a plurality of dies mounted on saidrotary table and each having a shoulder formed at about the middleportion of the inner surface thereof, means for charging a powder intosaid die, means for placing a cylindrical container with a bottom ineach die from the upper side with the lower open end thereof facingdownward to rest on said shoulder and means for pushing the powder inthe die upward from the lower side to compression-mold the same withinsaid container.

The present inventors previously applied for a patent for a moldingapparatus of this type which is so constructed that containers carriedby an intermittently driven rotary table are successively placed into opposed relation to a die at a predetermined position and a powderpreviously charged in said die is-pushed into the container andcompression-molded therein at said position. Therefore, the apparatusmust be provided with a rotary table for carrying the containers.

The present invention contemplates the provision of an apparatus whichis capable of compression-molding a powder into a predetermined shapewithin containers efficiently, without necessitating the provision of arotary table or the like for carrying the containers, by inserting acontainer into a die with the open end thereof facing downward, whichdie is previously charged with a powder, and moving the powder upwardinto the container and compression-molding the same therein whileholding said container in said die.

The first object of the present invention is to form a molding of apowder in a container, particularly the molding of a positive electrodedepolarizer in a cell container, in tight contact therewith bycompression molding, without permitting the powder to scatter andwithout adversely affecting the dimensional accuracy of the container.

The second object of the invention is to prevent the moldings ofa powderfrom varying from one another in density in the operation of chargingthe powder into the containers, by providing below each die a powdermolding mechanism including a molding tube and a molding center pindisposed in the axial hole of said molding tube, verticallyoscillating'said molding tube and said molding center pin independentlyof each other incident to the rotation of a rotary table after thepowder has been charged in said die and thereby equalizing theconsistency ofthe power in the die.

The third object of the invention is to provide for smooth rotation ofthe rotary table by providing cushion means below each die so that saiddie maybe movable vertically against the biasing force of said cushionmeans, and thereby preventing the pressure of container pressing meansfrom exerting on the rotary table in the compression-molding of thepowder within the container.

A further object of the invention is tocarry out the steps of chargingthe power into a container, compression-molding the power withinthecontainer and inwardly curling the open end of the containersuccessively continuously, by operatively engaging an auxiliary rotarytable with a main rotary table provided with dies and moldingmechanisms, through intermeshing gear teeth formed on the peripheralsurfaces of said respective rotary tables, and providing curling meansto effect said curling operation in operational relation to saidauxiliary rotary table.

These and other objects, features and advantages of the presentinvention will become apparent from the following detailed descriptionwhen taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view, partially broken away, of an embodiment ofthe apparatus for compressionmolding a powder within containersaccording to the present invention;

FIG. 2 is a diagram showing the position A H of the molding mechanismsprovided on the main rotary table and the positions I L ofthe containergripping means provided on the auxiliary rotary table of the apparatusof this invention, and also showing the change in relative position ofthe molding mechanisms and the container gripping means incident torotation of said respectiverotary tables;

FIG. 3 is a cross-sectional view of the powder molding mechanismprovided on the main rotary table;

FIGS. 4 to 10 are views showing the process of the compression-moldingoperation stepwise from the time when a powder is charged into the dieto the time when the powder is compression-molded in a container, saidoperation being carried out as the die is shifted from the station M tothe station S successively incident to rotation of the main rotarytable; and

FIG. 11 is a cross-sectional view of curling means by which the open endof the container is curled inwardly with the powder molded therein in apredetermined shape.

According to the present invention, there is provided a powder moldingapparatus comprising a base plate, an upright support column mounted onsaid base plate, a rotary table rotatably mounted on said support columnand being rotated intermittently, a plurality of dies provided on saidrotary table in circumferentially equally spaced relation, each of saiddies being open at the upper and lower ends thereof and having ashoulder formed at about the middle portion of the inner surfacethereof'for supporting the open end of a cylindrical container with abottom which will be inserted into said die with said open end facingdownward, a powder molding mechanism provided below each die, saidmolding mechanism including a vertically movable molding tube which willbe inserted into the axial hollow of said die from the lower open end tocompress a powder charged in the die and a vertically movable center pinextending through said molding tube with the top end thereof locatedwithin said die, powder charging means for charging the powder into saiddie through the upper open end at a predetermined position, containerfeed means for placing said container in the powder-charged die throughthe upper open end at a predetermined position and pressing means fordepressing said container when the powder charged in the die is movedinto the container and compressionmolded into a predetermined shapetherein by the action of said powder molding mechanism; said powdercharging means, said container feed means and said pressingmeans beingprovided above said rotary table.

As an embodiment of the present invention, an apparatus forcompression-molding a positive electrode depolarizer in a predeterminedshape within a cell container will be described with reference to thedrawings.

The apparatus of the present invention illustrated in the drawingsincludes two rotary tables, i.e. a main rotary table 1 and an auxiliaryrotary table 2. The main rotary table 1 is provided with a plurality ofmolding mechanisms to be described later in circumferentially equallyspaced relation, while the auxiliary rotary table 2 is provided withsecondary working mechanisms, e.g., curling mechanisms, for cooperationwith said respective molding mechanisms. More specifically, the mainrotary table 1, as shown in FIG. 2, has the molding mechanisms providedat eight locations A H which are equally spaced circumferentially, eachof said molding mechanisms being constructed as shown in FIG. 3.Further, the main rotary table 1 is formed with gear teeth on theperipheral surface thereof, which are in engagement with gear teethformed on the peripheral surface of the auxiliary rotary table 2, and isrotated intermittently in a clockwise direction as indicated by thearrow in FIG. 2, through an angle of 45 in each movement. The auxiliaryrotary table 2 has gripping means provided at four locations I L alongthe periphery thereof in equally spaced relation, and is rotatedintermittently by the main rotary table 1 in a counterclockwisedirection as indicated by the arrow, through an angle of 90 in eachmovement.

As shown in FIG. 1, the apparatus also has eight working stations M Tarranged in circumferentially equally spaced relation adjacent to theperiphery of the main rotary table 1 and each of the molding mechanismsis shifted from one working station to another incident to theintermittent rotation of the main rotary table 1. Likewise, fourstations U X are provided in circumferentially equally spaced relationadjacent the periphery of the auxiliary rotary table 2 and each of thegripping means is shifted from one station to another incident to theintermittent rotation of the auxiliary rotary table. The station S andthe station U are located in opposed relation to each other.

Now, various mechanisms of the apparatus associated with the main rotarytable 1 and the auxiliary rotary table 2 will be described withreference to FIGS. 1 to 3.

Numeral 3 designates a die which is provided at each of the locations AH of the main rotary table I and fixed in position by a flange member 4with the top surface flush with the upper surface of said main rotarytable. The die 3 consists ofa container adapted to receive a cellcontainer 5 and is positioned with the bottom end located on the upperside and the open end located on the lower side. Below the die 3 isprovided another die 7 in adjoining relation thereto. The die 7 has anaxial hole of adiameter equal to the inner diameter of the cellcontainer formed therein for receiving a powder (positive electrodedepolarizer), and also has a shoulder 6 formed at the contacting surfacewith the die 3.

The die 7 is vertically movably mounted in a sleeve portion 9 formed atthe center of a fixed body 8 of the molding apparatus which is locatedbelow the main rotary table 1. The open lower end of the sleeve portion9 is closed by a closure member 10 which has a throughhole'formedcentrally thereof, and a coil spring 11 is providedin said sleeveportion with one end bearing against said closure member and the otherend against a shoulder 12 formed on the peripheral surface of the die 7.Thus, it will be seen that the die 7 is urged upwardly by the biasingforce of the spring 11.

The dies 3 and 7 may be made separately and united integrally with eachother so as to form the shoulder 6, but alternatively they may be madeas a unitary piece having an axial through-hole and the shoulder 6 atabout the mid portion of the peripheral wall of said through-hole.

The flange member 4 serves to regulate the position of the die 3 so thatthe top surface of the die may be flush with the upper surface of themain rotary table 1, and can be removed from said main rotary table whenthe die is desired to be replaced upon wearing of the same.

Numeral 13 designates a molding tube with the lower end screw-threadedinto a bushing 14 secured to a sliding member 15 and the top end thereofextending into the axial hole of the die 7 through the lower endthereof. Numeral l6 designates a washer and 17 designates a bearingformed on each side of the sliding member 15. A pair of guide rods 18,18 are each fixed to the body 8 of the molding apparatus at the top endand extend downwardly through the bearing 17, so that said bearing ismovable vertically by being guided by the guide rod. Numeral 19designates rollers rotatably connected to each side of the lower endportion of the sliding member 15. These rollers 19 are provided forcontrolling the position of the molding tube 13 through the slidingmember 15, by engaging guide means at a predetermined position as willbe described later.

Numeral 20 designates a molding center pin extending through the moldingtube 13. The molding center pin 20 has an axial vent hole 20' and isfixedly connected at its lower end to a beam 22 which is verticallymovable along a vertical slot 21 formed in the sliding member 15. A pairof rollers 23,23 are provided at the opposite ends of the beam 22 andone of said rollers 23' rolls on a guide rail to be described later andcauses the center pin 20 to progressively move upward according to apositional change of said guide rail. The amount of movement b of theroller 23' caused by the guide rail is the distance which the top end ofthe center pin 20 travels from the interior of the die 7 to reach theinner bottom surface of the cell container 5. Both of the rollers 23, 23are oscillated vertically by engaging engaging members to be describedlater, whereby the powder is charged satisfactorily in the die 7.

The amount of movement h ofthe molding tube 13 is a distance necessaryto charge and mold the powder in the cell container 5 and to push saidcell container upward from the die 3 upon completion of the molding.

As stated previously, the main rotary table 1 and the auxiliary rotarytable 2 are operatively associated with each other with the gear teethformed on the peripheral surfaces thereof intermeshing, so that when oneof them is rotated intermittently, the other one is also rotatedintermittently regularly relative to said one rotary table. These tworotary tables 1 and 2 are rotatably mounted on support columns 25, 25respectively which stand upright on a base plate 24.

For rotating the main and auxiliary rotary tables, a motor is providedon the underside of the base plate 24 and the drive of the motor istransmitted to one of said rotary tables through a suitable reductiongearing and intermittent motion mechanism. In the embodiment shown, theauxiliary rotary table 2 is operatively connected to the motor to bedriven therefrom and the main rotary table 1 is rotated by the auxiliaryrotary table 2. Above the center of the main rotary table 1 is provideda cam 26. The cam 26 is rotated by a driving system, independent of thatfor the rotary tables 1 and 2, to impart a horizontal vibration to threepowder supply hoppers 27, 28 (and one provided above the station M,though not apparent in the drawings) through transmission levers 29.

Numeral 30 designates a container feed lever provided near the leadingend of container guide means 31 for placing the cell container 5 intoeach die 3, and numeral 32 designates a rotary brush provided at amidportion of the container guide means 31 for advancing the cellcontainers. Numeral 33 designates a press provided above the station R.The press 33 includes a ram 34 which will be lowered, when the rotarytable 1 has stopped rotating at the Station R, to engage the bottom wallof the container 5 and the upper surface of the die 3 and hold saidcontainer against upward movement relative to the rotary table 1 underthe molding pressure acting on the container from the underside.

Numeral 35 designates the container gripping means provided on theauxiliary rotary table 2 at the locations 1- L respectively. Eachcontainer gripping'means 35 is composed of a pair of opposed arms 36,36' which are formed with a notch in the confronting surfaces thereof.One of the arms 36 is pivotably connected and the other arm 36 isfixedlyconnected to the rotary table 2. The pivotable arm 36 is urgedagainst the fixed arm 36 by a spring 38 to keep the gripping portion 37closed at the outer end portions of the respective gripping arms.

The pivotable arm 36 of the gripping means 35 is opened against thebiasing force of the spring 38 by an operating member when said grippingmeans is located at the station U, and thereby the gripping portion 37is opened slightly so that the gripping arms can grip the container 5from both sides without interfering with the upward movement of saidcontainer and hold the same against downward movement together with themolding tube 13 when said molding tube is lowered. Numeral 39 designatesthe curling means by which the open edge of the container 5 is curledinwardly after the powder has been molded into, a predetermined shapewithin the container. The curling means is provided at the station V andcomprises, as shown in FIG. ll, a ram 40 for pushing the bottom wall(the top side) of the container 5, with said container 5 being held bythe gripping means 35, and a curling die 42 provided below the ram 40 inopposed relation thereto and having a cavity 41 of a predetermined shapeformed therein, in which the open edge (the lower side) of the containeris curled inwardly as shown.

Reverting to FIG. 1, numeral 43 designates a plurality of U-shapedengaging members provided on the base plate 24. These engaging members43 engage the rollers 23, 23 provided on both sides of the beam 22 andcause the center pin 20 to oscillate vertically through said beam. Eachof the engaging members 43 is operatively connected to a lever mechanism46 at the lower end of a shaft 45 thereof and said lever mechanism 46 isoperated by a rotary cam 47. Numeral 48 designates a spring to bias thelever mechanism 46 constantly upwardly. Therefore, the engaging members43 is also constantly biased upwardly by the spring 48.

The roller 23' which is one of the two rollers provided on the beam 22is located in the annular guide rail 49 having a U-shaped cross-sectionand rolls therein while being guided thereby. If the roller 23' were tobe still located in the guide rail 49 when the other roller 23 has beenbrought into engagement with the engaging member 43, it would beimpossible for the roller to oscillate vertically. Therefore, the guiderail 49 is partially broken at locations where the roller 23 engages therespective engaging members 43, so that the roller 23 can oscillatevertically together with the engaging member 43. Namely, the engagingmembers 43 are provided in a pair for engagement with both of therollers 23, 23' and one of the engaging members which engages the roller23 is provided in the borken portion of the guide rail 49 to constitutepart of said guide rail.

Therefore, when the rollers 23, 23' are in engagement with therespective engaging members 43, the vertical oscillation imparted tosaid engaging members is transmitted to the beam through the respectiverollers and thence to the center pin to cause the top end of said centerpin to oscillate within the die 7. Thus, the guide rail 49 is broken atthe locations where the engaging members 43 are provided. However, inorder to attain satisfactory charging of the powder into the die 7, itis necessary to raise the center pin 20 progressively as the main rotarytable 1 rotates. For this purpose, the height of the guide rail 49 isincreased by a predetermined rate stepwise rearwardly from the locationof the engaging member 43 (i.e. from the right to left when the table 1is rotated clockwise).

The operation of the apparatus, having the construction described above,for charging the compressionmolding a powder within the container willbe described hereinafter with reference to FIGS. 4 to 10.

Of the station M T of the apparatus, M O are the stations where a powder(positive electrode depolarizer) is charged into the dies 3 and 7 fromthe three hoppers. First of all, when the position A of the main rotarytable 1 is located below the hopper which is located above the station Mthough not apparent in FIG. 1, said hopper is oscillated horizontally bythe cam 26, so that the powder contained in the hopper is charged intothe dies 3 and 7 while being prevented from cross-linking and withoutbeing permitted to agglomerate. In this case, the rollers 23, 23' are inengagement with the first engaging members 43 provided below thatstation M, so that the center pin 20 having the top end thereof locatedwithin the die 7 is oscillated vertically and thereby the powder ischarged to the bottom of the die 7.

Then, the main rotary table 1 is rotated 45 in a clockwise direction,whereby the dies 3 and 7 having previously been held stationary at thestation M are shifted to the station N and the hopper 27 at said stationis similarly oscillated horizontally by the cam 26 to charge the powderinto the dies. The powder thus charged in the dies is well packedtherein by the action of the centerpin 20 which is again oscillated dueto engagement with the second engaging members 43. When the position Ais shifted from the station M to the station N incident to rotation ofthe main rotary table 1, the roller 23'-is progressively pushed upwardby the guide rail 49, so that thetop end of the center pin 20 is raisedwithin'the die 7 correspondingly.

Then, the rotary table 1 is rotated through another 45, so that theposition A is shifted from the station N to the station to locate thedies 3 and 7 below the hopper 28.The hopper 28 is oscillatedhorizontally by the cam 26 and the powder in said hopper is charged intothe dies. On the other hand, the roller 23' rolls in the guide rail 49while being guided thereby and engages the third engaging member 43,with the other roller 23 engaging the other one of the pair of engagingmembers. Therefore, the center pin 20 is again oscillated vertically,whereby the powder is packed more satisfactorily and any possibleirregularity in charging quantity can be corrected.

By the triple charging operations and oscillation described above, thepowder is packed tightly at a uniform density in a vertical direction.The center pin 20 is raised by the height b shown in'FlG. 3 due to theengagement between the rollers 23, 23 and the third engaging members 43,and is maintained at the same level even after the rollers 23, 23' rollonto the guide rail 49.

The table 1 is further rotated clockwise and the position A of the tableis shifted from the station 0 to the station P. At the station P, acontainer is placed in the die 3, flush with the die 3, by the containerfeed lever 30, with the bottom wall facing upwardly and the open endfacing downwardly. ln this case, the top end of the center pin 20 in thedie 3 is located at a level b higher than the original level and theopen end of the container 5 rests on the shoulder 6 formed at thejunction of the dies 3 and 7. Therefore, the container 5 is notpermitted to move deeper into the die and the top end of the center pin20 engages the inner bottom wall of the container 5, with the edge ofthe open end of said container resting on said shoulder 6.

This condition is maintained as such even after the position A isshifted from the station P to the station Q upon another 45 rotation ofthe table 1. The station Q is an idle station. When the position A isfurther shifted from the station Q to the station R, the ram 34 of thepress 33 moves downward and engages the bottom wall of the container 5to hold the container so that it may not be pushed upward from the die 3under an upward molding pressure.

In the lower portion of the molding apparatus, on the other hand, thelower end 50 of the sliding member is pushed up by an oil cylinder orthe like provided on the base plate 24, so that the molding tube 13 ismoved upward and the powder in the die .7 is moved into the container 5and compressed therein by the molding tube 13, whereby said powder ismolded into a cylindrical shape conforming to the shape of the taperedtop end portion of thec'enter pin 20. In charging the 7 powder into thecontainer 5, the air present in the, powder is released to the outsidethrough the axial hole 20' of the center pin 20. The lower portion ofthe sliding member 15 is moved by the pressing means a distance onlysufficient .to cause a flange 51 to move I upward to the position 51',which flange 51 is formed integrally on the molding tube 13. Uponcompletion of the compression-molding of the powder within the container5, the ram 34 of the press 33 is moved upward to the original positionand the container 5 is shifted from the station R to the station S whilebeing carried on the table 1 rotating 45 in a clockwise direction.During shifting of the container 5 to the station S, the top end of themolding tube 13 is maintained at the same level as it was at the stationR, by the pressure from the pressing means. The center pin 20 isslightly lowered at the station R upon completion of thecompressionmolding and maintained in that position to facilitate theremoval of the container 5 at the following station S.

When the table 1 is stopped to locate the container 5 at the station S,they lower end portion 50 of the sliding member 15 is pushed upward bythe pressing means and the flange 51 of the molding tube 13 is furthermoved upward from the position 51' to the position 51", that is theposition a distance of h higher than the original position, whereby thecontainer 5 is pushed up from the die 3 by the force of the molding tube13 acting on the molded powder in said container. The container 5 thuspushed up is gripped in the gripping por tion 37 of the gripping means35 which is provided on the auxiliary rotary table 2 and located abovethe container 5. Of course, the center pin 20 is also move up incidentto that upward movement of the molding tube 13. The container 5 grippedby the gripping means 35 and having the compression-molded powdertherein is carried to the station V, where the edge of the lower end ofthe container 5 is curled inwardly by the curling means 39 in the mannershown in FIG. 11. On the other hand, the die 3 which has been emptiedupon removal of the container 5 therefrom is shifted from the station- Sto the idling station T while being carried by the rotating table 1.During this period, a pair of rollers 19 provided on both sides of thelower portion of the sliding member 15 are gradually lowered from theelevated position to the same level as they are at the station M byreturn guide means and hence the molding tube 13 is also returned to theoriginal position. Of course, the center pin 20 is also lowered to thesame position as it was at the station M, like the molding tube 13.

On the other hand, the container 5 which has been subjected to thecurling operation at the station V while being held by the grippingmeans, is located at the idling station W by the table 2 upon rotationof said table through an angle of and then further shifted to thestation X, where it is slipped down from the gripping portion 37 of thegripping means 35 by a pressure applied thereto from the upper side anddelivered to the next working station.

In the compression-molding of the powder within the container 5, thecontainer 5 is held against upward movement by the ram 34, as statedabove. In this case, since the coil spring 11 is provided between theshoulder.l2 of the die 7 and the closure member 10 which closes thelower end of the sleeve portion 8, the dies 3, 7 or the flange member 4will not be subjected to an unnecessarily large pressure even if the ram34 is lowered excessively, the coilspring 11 only being compressed .asshown in FIG. 12. Therefore, the table 1 or the flange member 4 will notbe damaged by the ram,

nor will the rotation of the main rotary table I suffer frominterference.

According to the present invention, since the powder molding device isprovided below each ofa plurality of dies mounted on the main rotarytable, the steps of charging the powder into the die, transferring thepowder from the die into the container and compression-molding thepowder within the container, can be operated successively as thecontainer is shifted from one station to another while being carried bythe main rotary table. Therefore, the apparatus of the present inventionis highly adapted to mass production. It is also to be noted that inoperating the present apparatus, a smaller amount of the powder ispermitted to leak from the container than in case of the apparatus ofthe type wherein the container is held above the die. Another advantageof the present invention is that the residence time of the container ateach station can be minimized due to the fact that the amount ofmovement of the powder at each station in charging the powder into thedie or in transferring the powder from the die into the container issmall.

What is claimed is:

1. A powder molding apparatus comprising:

a base plate, a support column mounted upright on said base plate;

a rotary table rotatably mounted on said support column;

means for intermittently rotating said rotary table;

a plurality of dies supported in said rotary table in circumferentiallyequally spaced relation on said table, each of said dies having athrough-hole therein, said hole having a shoulder at about the middle ofthe inner surface of said hole for supporting the open end of acylindrical can body which has the other end closed, said die adapted toreceive said cylindrical can body in said throughhole in an invertedposition from the upper side of said die;

a powder molding mechanism provided below each die, said powder moldingmechanism comprising a molding tube adapted for inserting into itsrespective die upwardly from the underside of said die to force into thecan body supported in said die a powder charge, and a center pinextending through said molding tube and having a tapered upper portion,said center pin being vertically movable independently of said moldingtube, said center pin comprising an inner mold for forming a hollowvolume within the powder molded within said can;

powder charging means for charging powder into the hole in each die fromthe upper side ofthe die;

can feed means for inserting a cylindrical can body in an invertedposition in each die after said die has been charged with powder;

pressing means for pressing the can with a downward force against theupward force of said molding mechanism when the powder is inserted,compressed, and molded in said can by said molding mechanism;

vibrating means for vibrating the powder charging means while saidpowder charging means is charging powder into a die; and

further pressing means for moving said center pin and said molding tubeupwardly after said powder has been molded in said can to permit removalof said can containing the powder molded therein from engagement withsaid mechanism.

2. The power molding apparatus of claim 1, additionally comprisingvibrating means for causing a vertical oscillatory movement of thecenter pin when powder is charged into each die, whereby said powder ispacked in said die.

3. The powder molding apparatus of claim 1, additionally comprisingmeans for removing a can from said further pressing means after said canhas been removed from a die.

4. The powder molding apparatus of claim 1, wherein said dies areresiliently mounted in said rotary table by coil springs located betweensaid dies and said table, for resiliently absorbing any excessivedownward force applied to said die by said pressing means.

5. A powder molding apparatus comprising:

a base plate, a support column mounted upright on said base plate;

a rotary table rotatably mounted on said support column;

means for intermittently rotating said rotary table;

a plurality of dies supported in said rotary table in circumferentiallyequally spaced relation on said table, each of said dies having athrough-hole therein, said hole having a shoulder at about the middle ofthe inner surface of said hole for supporting the open end of acylindrical can body which has the other end closed, said die adapted toreceive said cylindrical can body in said throughhole in an invertedposition from the upper side of said die;

a powder molding mechanism provided below each die, said powder moldingmechanism comprising a molding tube adapted for insertion into itsrespective die upwardly from the underside of said die to force into thecan body supported in said die a powder charge, and a center pinextending through said molding tube and having a tapered upper portion,said center pin being vertically movable independently of said moldingtube, said center pin comprising an inner mold for forming a hollowvolume within the powder molded within said can;

powder charging means for charging powder into the hole in each die fromthe upper side of the die;

can feed means for inserting a cylindrical can body in an invertedposition in each die after said die has been charged with powder;

pressing means for pressing the can with a downward force against theupward force of said molding mechanism when the powder is inserted,compressed, and molded in said can by said molding mechanism;

coil springs located between said dies and said table resilientlymounting said dies in said rotary table for resiliently absorbing anyexcessive downward force applied to said die by said pressing means;

vibrating means for vibrating the powder charging means while saidpowder charging means is charging powder into a die;

further vibrating means for causing a vertical oscillatory movement ofthe center pin when powder is charged into each die, whereby said powderis packed in said die; and

powder molding

1. A powder molding apparatus comprising: a base plate, a support columnmounted upright on said base plate; a rotary table rotatably mounted onsaid support column; means for intermittently rotating said rotarytable; a plurality of dies supported in said rotary table incircumferentially equally spaced relation on said table, each of saiddies having a through-hole therein, said hole having a shoulder at aboutthe middle of the inner surface of said hole for supporting the open endof a cylindrical can body which has the other end closed, said dieadapted to receive said cylindrical can body in said through-hole in aninverted position from the upper side of said die; powder moldingmechanism provided below each die, said powder molding mechanismcomprising a molding tube adapted for inserting into its respective dieupwardly from the underside of said die to force into the can bodysupported in said die a powder charge, and a center pIn extendingthrough said molding tube and having a tapered upper portion, saidcenter pin being vertically movable independently of said molding tube,said center pin comprising an inner mold for forming a hollow volumewithin the powder molded within said can; powder charging means forcharging powder into the hole in each die from the upper side of thedie; can feed means for inserting a cylindrical can body in an invertedposition in each die after said die has been charged with powder;pressing means for pressing the can with a downward force against theupward force of said molding mechanism when the powder is inserted,compressed, and molded in said can by said molding mechanism; vibratingmeans for vibrating the powder charging means while said powder chargingmeans is charging powder into a die; and further pressing means formoving said center pin and said molding tube upwardly after said powderhas been molded in said can to permit removal of said can containing thepowder molded therein from engagement with said powder moldingmechanism.
 2. The power molding apparatus of claim 1, additionallycomprising vibrating means for causing a vertical oscillatory movementof the center pin when powder is charged into each die, whereby saidpowder is packed in said die.
 3. The powder molding apparatus of claim1, additionally comprising means for removing a can from said furtherpressing means after said can has been removed from a die.
 4. The powdermolding apparatus of claim 1, wherein said dies are resiliently mountedin said rotary table by coil springs located between said dies and saidtable, for resiliently absorbing any excessive downward force applied tosaid die by said pressing means.
 5. A powder molding apparatuscomprising: a base plate, a support column mounted upright on said baseplate; a rotary table rotatably mounted on said support column; meansfor intermittently rotating said rotary table; a plurality of diessupported in said rotary table in circumferentially equally spacedrelation on said table, each of said dies having a through-hole therein,said hole having a shoulder at about the middle of the inner surface ofsaid hole for supporting the open end of a cylindrical can body whichhas the other end closed, said die adapted to receive said cylindricalcan body in said through-hole in an inverted position from the upperside of said die; a powder molding mechanism provided below each die,said powder molding mechanism comprising a molding tube adapted forinsertion into its respective die upwardly from the underside of saiddie to force into the can body supported in said die a powder charge,and a center pin extending through said molding tube and having atapered upper portion, said center pin being vertically movableindependently of said molding tube, said center pin comprising an innermold for forming a hollow volume within the powder molded within saidcan; powder charging means for charging powder into the hole in each diefrom the upper side of the die; can feed means for inserting acylindrical can body in an inverted position in each die after said diehas been charged with powder; pressing means for pressing the can with adownward force against the upward force of said molding mechanism whenthe powder is inserted, compressed, and molded in said can by saidmolding mechanism; coil springs located between said dies and said tableresiliently mounting said dies in said rotary table for resilientlyabsorbing any excessive downward force applied to said die by saidpressing means; vibrating means for vibrating the powder charging meanswhile said powder charging means is charging powder into a die; furthervibrating means for causing a vertical oscillatory movement of thecenter pin when powder is charged into each die, whereby said powder ispacked in said die; and further pressing means for moving said centerpin and said molding tube upWardly after said powder has been molded insaid can to permit removal of said can containing the powder moldedtherein from engagement with said powder molding mechanism.